Smoke point apparatus



Jan. '14, 1958 R; A. HUNT, JR., ET AL I 2,819,606

SMOKE POINT APPARATUS 5 Sheets-Sheet 1 Filed Dec. 19, 1955 Russell A. Hunt, Jr.

Frederick W fiakowsky INVENTORS.

ATTORNEY Jan. 14, 1958 1 R. A. HUNT, JR., ET AL 2,819,606

SMOKE POINT APPARATUS Y Filed Dec. 19. 1955, s Shets-Sheet z II I I u W am 1 28 52 27 'f 25 7 l I I l I l5 .-/2 l o 1 I Fig. 2

1 i l I LE2 i I Russell A. Hunt, Jr.

Frederick W Rama's? INVENTOR /0 v v N BY ATTORNEY Jan. 14, 1958 R. A. HUNT, JR., ET AL 2,819,605

SMOKE POINT APPARATUS 3 Sheets-Sheet 5 Filed Dec. 19, 1955 LAMP l. I? LAMP 5 bSQl Nkbh 0 /0 20 30 40 50 60 70 .80 .90 I00 I10 I I I I I I NEW LAMP SMOKE POI/VT (In/n.)

Russell A. Hun! In Frederick ll! Ralowsky K INVENTORS.

BY Ma. 9%

ATTORNEY United States This invention relates to an apparatus for determining smoke point of hydrocarbon fuels.

One of the many control tests used in the petroleum industry to maintain a uniform quality of product is the smoke point test in which a small quantity of the fuel to be tested is burned in a specified test lamp in which the .flame height can be adjusted. The smoke point is defined as the height in millimeters of the highest flame produced without smoking. The higher the smoke point the better the fuel burning quality and the lower the sooting tendency. Thus, smoke point is used to define minimum acceptable burning quality and it is of particular importance that the lamp used provide maximum sensitivity in the range where minimum quality requirements fall.

Smoke points have been used since about 1930 as a measurement of quality of kerosene used as an illuminating oil. More recently, smoke point has been used as a measure of fuel burning quality as, for example, the sooting tendency of heating oils and jet aircraft fuels. A standard method of test was described before the World Petroleum Congress in 1933. In such a test the lamp is lit, adjusted to give a smokeless flame, and allowed to burn minutes to reach equilibrium. The flame is then turned up until it is definitely smoking and then lowered slowly until the smokey tail just disappears. The height of the flame at this point is taken as the smoke point. A

tentative ASTM test based upon this test procedure has been proposed for use on jet fuels and is designated as ASTM D 132254T.

Various types of lamps have been used in smoke point studies but no one of them has been entirely satisfactory from all standpoints. For example, smoke point lamps heretofore available do not permit a great enough spread in smoke points between different fuels and do not provide adequate means for minute adjustments of the wick which are necessary for the desired sensitivity and accuracy.

The increased emphasis on carbon deposition in jet engines has increased substantially the need for methods for specifying fuel burning quality. Smoke point is currently used in jet fuel specifications and since minimum quality is specified it is desirable to use a lamp having maximum sensitivity, in this range, and which provides a precise method of determining minimum jet fuel burning quality. However, smoke points obtained with one lamp must correlate well with those obtained with other lamps now in use.

It is, therefore, a primary object of the invention to provide a smoke point apparatus having maximum sensitivity for indicating the greatest spread in smoke points. An

additional object is to provide a lamp adapted for use on a wide variety of fuels. A further object of the invention is to provide a lamp with an accurate means for making precise adjustments in the wick height. A further object is to provide an apparatus which is rugged and of simple construction. Still another object, of the invention is to provide an apparatus which is substantially foolproof in its operation so that it may be used by personnel without specialized technical training. Another object is to provide an apparatus giving results which can be correlated with smoke points obtained on other lamps. These and other objects of our invention will be understood from the description thereof which follows.

Although a number of lamps have been used in smoke atent O Patented Jan. V14, 1958 point studies and although test procedures have been devised using such lamps, there are not available such information and data as would permit one to design a lamp with optimum sensitivity. Consequently, we have made studies to ascertain the physical variables of lamp design which affect smoke point. The smoke lamp devised by us gives the best distinction between fuels consistent with ease of operation and adaptability for use in routine testmg.

Briefly, according to our invention, we provide a lamp having a wick diameter of 7 inch; chimney diameter 22 millimeters; chimney height 200 millimeters; and air screen height 28.6 millimeters. A wick guide height is 1 inch. Our lamp also embodies an improved mechanism for raising and lowering the wick within the wick guide and chimney.

Further details of construction and advantages of our invention will be described in conjunction with a preferred embodiment illustrated in the accompanying drawings wherein:

Figure l is a perspective of the assembly;

Figure 2 is an elevation, partly in section, of the apparatus of Figure l; and

Figure 3 presents correlation data with other lamps.

Referring to the drawings, the apparatus comprises a base 10 on which is mounted the tubular support or housing 11 containing a threaded shaft 12 and a travelling block 13. A sleeve 14 supports the cylindrical oil holder 15 closed at its upper end by the wick holder 16 comprising plug 17 and the tubular extension 18 which is slideably retained by the wick guide 19. The wick 20 is movable Within the wick guide 19 which is surrounded by the air screen 21 and above which is the glass chimney 22. The chimney support 23 is provided with a millimeter scale 24 for measuring the flame height. The tubular housing 11 includes a cantilever beam 25 which in turn supports the chimney brace 23, the air screen 21, and the wick guide 19.

The oil holder 15 and the wick holder 16 are supported in movable sleeve 14 by a pin 26 and a slot 27. The sleeve 14 is held by clamp arm 28 and is positioned by the rotation of the threaded shaft 12 upon which the travelling block 13 rides. Thus, a wick 20 placed in the wick holder 16 can be moved within the wick guide 19 to project a controlled distance into the chimney 22 to adjust the flame height. The lower portion of the wick 20 is, of course, immersed in the fuel within the holder 15.

The wick guide 19 comprises a tube which may be threaded into a bore in the beam 25. The chimney 22 is of glass and the air screen 21 may suitably comprise 20 mesh stainless steel; screens with a height of about 1.125 inches being preferred for a chimney having a diameter of 22 mm. With such an assembly we use a wick guide 19 having a height of about 1 inch and a wick 20 having a diameter of about A inch.

The threaded shaft 12 is rotated by a pair of helical gears 29 which are controlled by knob 30. In this manner, a relatively large movement of the control knob 30 is translated into a small and precise movement 'of the wick 20.

V as the smoke point.

Repeatability with our described lamp is as good as with the standard lamps heretofore used and duplicate determinations by the same operator do not differ by more 3 than 1 mm. Repeatability between operators is within :1 mm.

Results obtained on our lamp have been compared with the Institute of Petroleum lamp, hereinafter referred to as the I. P. lamp, and the Factor lamp, both widely used heretofore in making smoke point tests to determine the relative sensitivities of the three lamps. Fuels with a smoke point of a wide range of values are used in these correlations. Number 2 fuel oil components and blends were used to provide smoke points in the range of to 30 mm.; kerosenes, jet fuels, and gasolines in the range from 30 to 60 mm; and pure hydrocarbons in the range from 60 to 150 mm.

Correlations of the values from the I. P. and Factor lamps with those obtained with a lamp of our design are as shown in Figure 3. Our described lamp is more sensitive to fuel quality and gives greater spreads of values between fuels, the lamp constructed to our invention increasing the spread of the I. P. lamp by a factor of about 2 to 1 at low flame heights and as much as 4 to l at greater heights. Furthermore, our lamp has a range of from 5 to 150 mm. whereas the range of prior lamps is much smaller, the I. P. for example not being able to determine smoke points greater than 50 mm.

Although our invention has been described with reference to a preferred embodiment thereof, this is by Way of illustration only. Accordingly, it is contemplated that modifications can be made in the apparatus and the mode of using the apparatus without departing from the scope ,of our invention.

What we claim is:

l. A lamp for determining the smoke point of fuels which comprises in combination a housing, a movable support member supported by said housing, a chimney support fixed to said housing, a transparent chimney held by said chimney support, an air screen below said chimney and on said housing, wick guide means arranged below .said chimney in said housing, a fuel holder of generally cylindrical shape and having an open top, a wick holder fixed across said open top, said wick holder having a tubular projection in slidable engagement with the interior ofsaid wick guide, a pin on the exterior wall of said fuel holder engageable with a slot in said support member whereby said wick may be adjustably projected through said wick guide, and a millimeter scale for measuring the .flame height in said chimney.

2. A smoke point lamp including a chimney having a .diameter of 22 millimeters and a height of 200 millimeters,

an-air screen subjacent to said chimney having a diameter of 22 millimeters and a height of 28.6 millimeters, a memguide means in said bore and extending about one inch therefrom into said air screen, said wick guide means being adapted to receive a wick member having a diameter of about /1 inch, a wick holder through which said wick member is threaded, a recess in said wick guide means adapted to slidably receive the said wick holder, an oil reservoir cylinder closed at its upper end by said wick holder, the reservoir cylinder, the wick holder, and the'wick member together forming a unit which is adjustably supported below said wick guide means with a length of the wick member projecting therethrough, the means for adjustably positioningthe said unit comprising a threaded shaft, a travelling block on said shaft, a sleeve carried by said block and supporting said unit, gear means .for rotating said shaft, and a control knob for said gear means whereby a largemovement of the control knob is :translatedinto a precise wick movement.

3. In a smoke point lamp including a chimney means, a wick guide means, and a wick assembly associated with an oil reservoir, the improvement which comprises a fixed tubular wick guide, a movable sleeve means for supporting said wick assembly in an adjustable position with respect to the upper end of said wick guide, said sleeve support being adjustably positioned by means of a travelling block on a threaded shaft which is rotated by manually controlled gear means.

4. Combination fuel and wick holder means for use in a smoke point lamp which comprises an open-topped cylindrical chamber, a threaded plug for said open top, a tubular wick holder extending through said threaded plug and longitudinally of said cylindrical chamber, a wick member extending from within said chamber through said tubular holder, and means for adjustably supporting said holder with said wick member in an operative relation to the said wick holder.

5. A lamp for determining the smoke point of liquid fuels which includes in combination a lamp housing, a wick guide extending upwardly from said housing, a wick holder sleeve slidable within said wick guide, said wick holder being fixed to a cylindrical oil reservoir, means for adjustably supporting said reservoir within said housing with said wick holder projecting into said wick guide, a wick means extending from said reservoir through said holder and upwardly of said guide, a chimney means arranged about said wick guide on said housing, a major upper portion of said chimney means comprising a glass tube and a major lower portion thereof comprising a perforate cylinder of substantially the same diameter as the glass tube, the lower end of said tube terminating in a plane above the upper end of said wick guide, flame height scale means aligned with the upper end of said wick guide, and means for adjusting the position of said reservoir and hence said sleeve and said wick with respect to the upper end of said wick guide.

6. The apparatus of claim 5 wherein the said glass tube has a diameter of 22 millimeters and a length of 200 millimeters, the subjacent perforate cylinder has a diameter of 22 millimeters and a height of about 28.6 millimeters, the wickguide has a height ofabout 25.4 millimeters, and the wick has a diameter of about 8.0 millimeters corresponding to the inner diameter of the wick holder and of the upper end of said wick guide.

7. In a smoke point lamp including an oil reservoir, a wick assembly associated therewith, and a chimney the improvement which comprises a wick assembly including a tubular wick holder carried by the upper end of a cylindrical oil reservoir, a wick extending from said reservoir through said wick holder and projecting beyond the outer end thereof, a relatively fixed tubular wick guide, the lower portion of said wick guide having an inner diameter great enough to accommodate an end of said wick holder and the upper end of said wick guide being of smaller inner diameter adapted to receive snugly the said wick, adjustable means for supporting said reservoir in alignment with said wick guide, chimney means disposed about and above said wick guide, said chimney means comprising an upper major portion of a transparent imperforate tube wholly above theupper end of said wick guide and a subjacent minor perforate tube portion extending between the lamp housing and the lower end of said imperforate tube, and flame height scale means paralleling said chimney and having a scale extending upwardly from the top of said wick guide.

References Cited in the file of this patent UNITED STATES PATENTS Becker Nov. 30, 1886 OTHER REFERENCES 

